Drafting pen



July 8, 1958 c. B. HODGES 2,842,100

DRAFTING PEN Filed Aug. 14, 1957 United States Patent DRAFTING PEN Clarence Burtes Hodges, Hazel, Ky. Application August 14, 1957, Serial No. 678,112

1 Claim. (Cl. 120-1095) This invention relates to drafting pens.

In order to draw a wide line with a drafting pen of the type using two blades it is necessary to draw two or more adjacent fine lines. In drawing wide lines by this method, care must be exercised in drawing the fine lines adjacently to insure uniform width of line. Also, in attempting to draw a wide line with a drafting pen of the type described, difliculty is experienced in starting the line due to the ink tending to pull upward between the two blades and away from the surface to be inked.

The principal object of this invention is to provide a drafting pen enabling the drawing of wide lines with fewer strokes.

Another object of this invention is to provide a drafting pen permitting easier starting of lines due to less capillarity in the drafting pen for a given width of line.

A still further object of this invention is to provide a drafting pen which permits greater accuracy in wide lines as such lines can be drawn in fewer strokes.

With these and other objects and advantages in view, the invention consists of the new and novel combination, construction, and arrangement of parts as hereinafter more fully described, set forth in the claim appended hereto, and disclosed in the accompanying drawings forming part hereof, wherein:

Figure 1 is a side elevation of a drafting pen illustrating the general relation of the cooperating parts according to the present invention.

Figure 2 is a front elevation of a drafting pen with the handle portion shown fragmentarily.

Referring to the drawings, A indicates a drafting pen which may be a ruling pen or the pen portion of a compass, a ruling pen being described and illustrated in the present application. The pen includes a shank portion 1 carrying the pen unit 2 and handle 3, shank 1 of pen A having a cylindrical portion 19, said portion 19 having an annular groove 20, friction between edge 22 of groove 20 and cylindrical bore 21 in end of handle 3, and friction between said cylindrical portion 19 and bore 21 causing handle 3 to remain in place when pressed onto cylindrical portion 19 of shank 1 of pen.

The pen unit 2 is comprised by the blades 4, and 6, the latter being intermediately located between blades 4 and 5, and in a relatively stationary position with regards to blades 4 and 5. The points 23 and 24 of blades 4 and 5 are simultaneously equidistantly adjustable toward and away from point 25 of intermediate blade 6 by adjusting screw 7, adjusting screw 7 being fixed in its longitudinal axis in relation to intermediate blade 6, and having opposed screw threads 8 and 9 on opposite sides of intermediate blade 6, the opposing threads being screw threaded into blades 4 and 5 to simultaneously move said blades 4 and 5 away or toward blade 6 depending on direction of rotation of adjusting screw 7.

Adjusting screw 7 has a bearing portion, preferably a reduced portion 13, approximately midway its length, sides 14 and 15 of said reduced portion abutting around slot 10 a portion of sides 16 and 17 of intermediate blade 6. Slot 10 of intermediate blade 6 is larger than the diameter of reduced portion 13 but smaller than the threaded sections 8 and 9 of adjusting screw 7 to prevent binding between portion 13 and slot 10 when the outer blades 4 and 5 are opened or closed and yet offer bearing against sides 16 and 17 of intermediate blade 6 by sides 14 and 15 of adjusting screw 7.

According to the present invention the intermediate blade 6 is slotted at 10 to permit assembly of adjusting screw 7 into intermediate blade 6 and by rotating adjusting screw 7, blades 4 and 5 are then screwed onto the adjusting screw 7, after which, adjusting screw knob 11 is attached. The preferred method of attaching said knob 11 being to press fit knob 11 onto a reduced portion 12 of adjusting screw 7.

Intermediate blade 6 has a recess 18 to facilitate filling the pen with inking fluid, the opening of an ink dispenser being placed into the recess 18 enables spaces between blades 4 and 6 and between blades 5 and 6 to be more readily filled with ink.

The invention is of course subject to variation of construction within the principle illustrated and it will be apparent that the simple construction disclosed permits the drawing of wider lines with one stroke of the pen than is possible with other types using two blades.

What I claim as my invention is:

A drafting pen comprising a pen unit having a shank portion containing two exterior blades and an intermediate blade, said intermediate blade being comparatively rigid with respect to shank and the two exterior blades, points of said exterior blades adjustable toward and away from point of said intermediate blade, said pen unit normally being carried by a handle, means for detachably connecting said pen unit to handle, including an annular grooved cylindrical portion on shank to fit into bore in handle, a handle bored to accept said grooved cylindrical portion of shank, an adjusting screw attached and fixed in its longitudinal axis onto the intermediate blade, said adjusting screw having its opposite ends screw threaded with opposed screw threads and screw threaded into the two exterior blades thereby urging points of said exterior blades simultaneously equidistantly away or toward point of said intermediate blade when said adjusting screw is turned, a recess in said intermediate blade to aid in filling the pen with inking fluid.

References Cited in the file of this patent UNITED STATES PATENTS 364,282 Orlob June 7, 1887 2,485,280 Grace Oct. 18, 1949 2,489,870 Dzus Nov. 29, 1949 

